U.S. Pat. No. 6,750,815 discloses a navigational system for surface vessels that provides warning of impending grounding occurrences. A data base of bottom contours and submerged obstructions is compared to various indicators of the surface vessel's position and motion to provide alerts and to display bottom hazards ahead of the vessel.
U.S. Pat. No. 7,476,862 discloses two sensor units mounted on opposite sides of a transom of a boat and directed to a common location behind the boat. The field of view of the two sensors overlaps behind the marine propulsion unit of the boat to detect the presence of a heat emitting object, such as a mammal. Housing structures contain infrared sensing elements, lenses, and light shields. Signals from four infrared sensing elements are received by a controller which reacts, with an alarm signal, when at least two of the four sensors detect a heat emitting object within their individual fields of view. False triggering can be reduced by not providing an alarm signal if only the two most inboard sensors detect the heat emitting object.
U.S. Pat. No. 5,274,378 discloses a relative velocity indicator system for assistance in the docking of vessels using a radar sensor providing a relative velocity signal indicative of the relative velocity between a ship and a reference, such as a dock. A wireless transmitter associated with the radar sensor receives said relative velocity signal and transmits a signal indicative of said relative velocity signal. A portable receiver and indicator unit carried by the captain of the vessel has a receiver for receiving the transmitted signal and an indicator arranged to receive, from said receiver, a receiver signal indicative of the transmitted signal and, thereby, of the relative velocity signal for indicating the relative velocity between ship and reference.
U.S. Pat. No. 3,707,717 discloses a system for generating correction command signals relative to the berthing velocity profile of a vehicle in approach of a docking position. A Doppler radar system including a radar transceiver projects signals between the docking position and the vehicle and respondingly generates Doppler shift frequency signals indicative of the velocity of the vehicle and the relative displacement thereof. A radar counter having preset initial counts stored therein indicative of anticipated initial berthing conditions, responds to the frequency shift signals by counting down from the initial counts in accordance with the Doppler shift. Means is included for updating the radar counter in accordance with actual conditions and includes a sonic detector which periodically projects sonic signals between the vehicle and the docking position and respondingly generates corrected count signals in accordance with the reflected sonic energy, indicative of actual distance of the vehicle to the docking position. Means is utilized which periodically transfers the corrected count signals to the radar counter, correcting for errors between actual and preset initial conditions.
U.S. Pat. No. 7,561,886 discloses a method by which a position of a marine vessel can be determined relative to a stationary object, such as a dock. Two position sensors are attached to a marine vessel and a microprocessor, onboard the marine vessel, computes various distances and angular relationships between the position sensors on the marine vessel and stationary transponders attached to the fixed device, such as a dock. The various dimensions and angular relationships allow a complete determination regarding the location and attitude of a marine vessel relative to the dock. This information can then be used by a maneuvering program to cause the marine vessel to be berthed at a position proximate the dock.
U.S. Pat. No. 3,690,767 discloses a docking system for large ocean-going vessels, which comprises a laser pulse range radar system having a laser transmitter and receiver, a retroreflector, and receiving and transmitting optics. Two such systems are disposed on a dock. The retroreflectors are disposed on the bow and stern of a vessel. The laser systems share a time interval meter, a computer, and a display panel. The lasers track the retroreflectors as the ship approaches the dock, and the time interval between the transmitted and received pulses is measured. Computations are made and the velocity of the approaching vessel, its distance from the dock, and the vessel position with reference to the dock are continually displayed. This information is then transmitted to the ship's captain.
U.S. Pat. No. 5,933,110 discloses a portable attitude determination apparatus and method that can be used with a ship docking system. At least two receivers on a vessel receive Global Positioning System (GPS) satellite data. GPS carrier phase measurements are used to determine attitude (i.e., roll, pitch and yaw angles) of a moving platform. The phase measurements are processed to determine a precise vector from one receiver phase center to the other. The azimuth and elevation of a baseline vector is then computed. Float ambiguities between the two receivers are determined, and are used to provide initial estimates of antenna baseline length and attitude. A search procedure is then employed to find the actual integer ambiguities. Only GPS observables are needed; no other external data input is required.
U.S. Pat. No. 6,268,829 discloses a Doppler Direction Finder comprising at least one antenna (52) spaced from a location point (53). The at least one antenna (52) is arranged in use to be rotated about the rotation point (53). The at least one antenna (52) is arranged to provide a first output signal comprising a signal received by said at least one antenna (52) combined with the Doppler Shift component. There are means (70) for providing a second output signal comprising the received signal without the Doppler Shift component. Processing means (54-82) process the first and second signals to obtain the Doppler Shift component. Determining means (88) determine from the Doppler Shift component the direction from which the received signal is received.
U.S. Pat. No. 6,492,933 discloses a dual channel microwave sensor that employs single sideband Doppler techniques in innumerable vibration, motion, and displacement applications. When combined with an active reflector, the sensor provides accurate range and material thickness measurements even in cluttered environments. The active reflector can also be used to transmit multi-channel data to the sensor. The sensor is a homodyne pulse Doppler radar with phasing-type Doppler sideband demodulation having a 4-decade baseband frequency range. Ranging is accomplished by comparing the phase of the Doppler sidebands when phase modulated by an active reflector. The active reflector employs a switch or modulator connected to an antenna or other reflector. In one mode, the active reflector is quadrature modulated to provide SSB reflections. Applications for the low-cost system include a mechanical motion/rotation sensor, a robust security alarm, a throat microphone, a stereo guitar pickup, a direction sensitive cardiac monitor, an electronic dipstick, a material thickness/dielectric sensor, a metal smoothness meter, a non-contact electronic readout, an RFID tag, silent “talking” toys, a passive-emitter data link, a beam interrupter, and a gold nugget finder.
U.S. Pat. No. 7,267,068 discloses a marine vessel that is maneuvered by independently rotating first and second marine propulsion devices about their respective steering axes in response to commands received from a manually operable control device, such as a joystick. The marine propulsion devices are aligned with their thrust vectors intersecting at a point on a centerline of the marine vessel and, when no rotational movement is commanded, at the center of gravity of the marine vessel. Internal combustion engines are provided to drive the marine propulsion devices. The steering axes of the two marine propulsion devices are generally vertical and parallel to each other. The two steering axes extend through a bottom surface of the hull of the marine vessel.
U.S. Patent Application Publication No. 2011/0138277 discloses a method of generating haptic effects on a device including detecting the presence of an object near an input area of the device and generating a haptic effect on the device in response to the presence detection.